1. Field of the Invention
The following relates in general to computer networks, and more particularly, to providing services in wireless telecommunication networks. The following is particularly useful for determining roaming rules for a mobile-subscriber terminal when the mobile-subscriber terminal roams into a private-wireless network from a public-wireless network, and vice-versa.
2. Description of Related Art
Public-wireline telecommunications carriers typically provide to their subscribers telecommunications and other networking services (collectively “services”) based, in a large part, on a particular geographical coverage area in which the subscriber resides or otherwise plans to operate. For example, a resident of municipality “A” may subscribe to public wireline carrier “A,” whereas a resident of another municipality may subscribe to public wireline carrier “B.” Consequently, a subscriber of carrier A cannot move to a coverage area of a foreign carrier, such as carrier B, and continue to receive services without changing their subscription to the foreign carrier. In other words, the subscribers of public wireline networks cannot roam.
On the other hand, a subscriber of a public-wireless and/or a satellite network (collectively referred to as a “public-wireless network”) may not only receive the services when operating in the coverage area of their subscribed-to network, but also when roaming in the coverage area of a foreign carrier's public-wireless network. To facilitate roaming, the carriers of the subscribed-to and foreign networks public-wireless networks normally negotiate roaming agreements. This is in addition to providing the technological requirements carry out supplying services to roaming mobile-subscriber terminals.
Such roaming agreements are particularly advantageous to the carriers of both the subscribed-to and foreign networks because the coverage area is based primarily on geographically-restrictive, governmentally-granted licenses for wireless spectrum. Thus, the roaming agreements allow the carriers of the subscribed-to and foreign networks to provide to their subscribers extended coverage areas, which can range from a small municipality to an entire country or even to a plurality of countries.
When the public-wireless networks are integrated with public wired networks, the combined networks provide domestic along with international coverage. Thus, the combined networks may include portions of a Public Switch Telephone Network (PSTN), the Internet, core and proprietary public networks, and/or wireless voice and packet-data networks (e.g., 1G, 2G, 2.5G and 3G telecommunication networks).
For many years, not only have businesses, Small Office/Home Office (SOHO) entities, and other organizations (collectively referred to herein as “enterprises”), but also private individuals have been using private telecommunications networks. Typically, these private networks terminate to public-wireline networks, but are not under the control of the carriers of the public-wireline networks. Advantageously, then, private networks provide the enterprises and private individuals with greater control over the network, which in turn allows customization of the services provided to the network's users and/or subscribers.
For example, many enterprises and private individuals have private-wireline-switching systems, such as private branch exchanges (PBXs) and/or media gateways. These private-wireline-switching systems manage communications (i) internally, i.e., among the subscribers of the private network, and (ii) externally, i.e., between the subscribers of the private network and subscribers of the public wireline or wireless networks. With the ability to manage internal communication free from the public-wireless and/or wireline networks, the private-wireline-switching systems can offer enhanced services such as call forwarding, caller id, etc., to its internal subscribers.
Recent advances in computer data networks, such as the ability to provide Voice-over-Packet communications, have provided the impetus for delivering telecommunication services over local area networks. Enterprises and private individuals are increasingly deploying private-wireless networks, such as wireless local area networks (WLANs). These WLANs may be deployed as stand-alone networks. Alternatively, the WLANs may be coupled to private-wireline-switching systems to connect to the public wireline networks.
Unlike the licensed spectrum used in public-wireless networks, WLANs in the United States have been and are being deployed using freely-available, allocated frequencies provided by the Unlicensed National Information Infrastructure (U-NII). Other countries have similar governmental grants for unlicensed frequencies.
Consequently, the WLANs have developed independent of the geographical restrictions normally associated with the licensed wireless spectrum. However, due to (governmentally-imposed and technological) power limitations, the coverage areas of such private networks are typically geographically limited. These geographically-limited coverage areas are commonly referred to as “hotspots.”
The coverage area of a hotspot may be, for example, a single building, a part of a building, or a complex of buildings and campuses, though, typically, such coverage does not cover large contiguous areas. The recently promulgated IEEE 802.11 standard defines a standard protocol for using frequencies allocated by the Unlicensed National Information Infrastructure (U-NII). Under various sections of the standard, the maximum coverage area for a given power and frequency range is defined. For example, a wireless access point conforming to IEEE 802.11b may be limited to providing coverage within a 150 foot radius, whereas a wireless access point conforming to IEEE 802.11g may be limited to providing coverage within a 175 foot radius.
Theoretically, wireless access points may be “daisy-chained” together through a wireline backbone, such as an intranet. Although a single wireless access point can be fairly inexpensive, providing enough wireless access points to cover large contiguous coverage areas and the corresponding infrastructure to support the wireless access points can be substantially expensive and difficult to implement.
Consequently, private-wireless networks are generally not integral to or integrated with other private and public-wireless networks. Even if the private-wireless network is coupled to such other private and public-wireless networks, any external communications are carried out according to rules set-up by the carriers of the other networks. Thus, neither the private-wireless carriers nor the public-wireless carriers currently offer services to their respective subscribers in the others' networks.
Consider, for instance, call forwarding services for a subscriber of a public-wireline network and a public-wireless network. When using the call forwarding services, calls placed to the user's work phone may be forwarded to the user's mobile-subscriber terminal. While this service is useful when the user is in the coverage range of the public-wireless network, it may not work when the user is far from the office and out of the coverage area of the public-wireless network. Thus, a user may be unable to receive important calls when operating outside the coverage area of a public-wireless network even though the user is within the coverage area of a private-wireless network.
One way to overcome this situation is to have a user independently subscribe to the public-wireless network and all the private-wireless networks that cover the area he or she plans to use. In many cases, subscribing to all these networks may require the user to have separate subscriber accounts, separate sets of services, separate mobile-subscriber stations (or a single multiple-technology terminal), and separate mobile-subscriber-station identifiers. Thus, this approach may be impractical. Even if implemented, the user may have certain services available only when operating in the public-wireless network that are not available when operating in the private-wireless networks.
Furthermore, with the abundance of inexpensive WLAN equipment and without the ability to keep others from using the spectrum (and deriving profits therefrom), the public-wireless network carriers historically have been reluctant to invest resources into WLANs. Coupling this with the technological differences between the architectures of the private-wireless and public-wireless networks, the carriers of the public-wireless and private-wireless networks have not generally entered into roaming agreements.
The lack of roaming agreements has prevented integration or harmonization of methods and systems for facilitating roaming between the public-wireless and private-wireless networks. But with the growing number of private-wireless networks and the subscribers' desires for coverage no matter where they are operating, there is a need to facilitate roaming between the public-wireless and private-wireless networks.